Just in case anyone is looking at this, who may have a similar setup to myself...
After reading a few other posts in the thread I removed whatever Net Framework had installed, being on the Windows XP platform, I made sure I had installed SP3, went back in and installed NET Framework 4.0 from the "dotNetFx40_Client_x86.exe".
Once again, subsequently, DWG TRueview would not install, still looking for NET Framework 4.0 SP1.
So i take it that the instance of NET Framework 4.0 installed from the above file does not include SP1 and that the instance of NET Framework 4.0 that installs from the web based installer (perhaps a later version?) can not install to a 32 bit platform....?
dunno, I'm just joining the dots here....